This competing renewal application seeks continuation of support for a post-doctoral training program that prepares talented individuals for independent research careers in the reproductive sciences. The program emphasizes guided research under the mentorship of established investigators, focusing on cellular and molecular approaches and the translation of research findings to human biology and/or clinical application. The multidisciplinary training faculty, drawn from the Schools of Medicine, Veterinary Medicine, Dental Medicine and the College of Arts and Sciences, represents the disciplines of Biochemistry, Biology, Cell and Developmental Biology, Genetics, Pathology, Pharmacology, and Physiology and the clinical disciplines of Obstetrics and Gynecology, Internal Medicine, Pathology and Pediatrics. Trainee candidates holding the Ph.D., M.D., V.M.D. or equivalent degree are selected based on excellence in their past research and academic pursuits, and their potential to become independent investigators. The training program actively seeks physician trainees and has an established curriculum that supplements their research training with didactic course work and may encompass a formal Ph.D. degree program. Under represented minority candidates are pursued with help from institutional resources. Appointments are made by consensus of the training faculty. Trainees select a mentor or mentors with approval of the program Executive Committee. Joint mentorship of trainees is encouraged based on the program's strong tradition of collaboration in research training and the clear benefits to the trainee of the broader scope of expertise afforded by this arrangement. In addition to mentored research, trainees participate in an extensive academic enrichment program that includes weekly research seminars, combined laboratory meetings and journal clubs. The faculty monitors trainee progress on a semi-annual basis, considering quality of research, productivity, and growth towards independence in this evaluation. Resources available to trainees include the Center for Research on Reproduction and Women's Health and its Molecular Biology and Biostatistics Core Facilities, the Mellon Foundation Center of Excellence in Contraceptive Development and the Medical Centers Office of Post-doctoral Research which sponsors a variety of programs to prepare trainees for academic careers as well as careers in industry. Trainees are generally supported by the grant for no more than two years; they are expected to submit applications for individual NRSA, K awards or equivalent fellowships to sponsor additional training. Trainees have had an excellent record for securing these awards. Based on the strength of the faculty, the past training record, and the available applicant pool, support is requested for a steady-state level of six trainees.